Speaker cooling

ABSTRACT

Embodiments are provided for cooling one or more components of a playback device using speaker vibrations that result from playback of inaudible audio. Movement of air molecules arising from the speaker vibrations may disperse heat away from the one or more components of a playback device. In an example implementation, a playback device detects that playback of audible audio content via at least one speaker has stopped, and in response to the detection, plays inaudible audio content to cause the at least one speaker to vibrate thereby inducing air movement within the playback device.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority under 35 U.S.C. §120 to, and is acontinuation of, U.S. non-provisional patent application Ser. No.15/063,305, filed on Mar. 7, 2016, entitled “Speaker Cooling,” which isincorporated herein by reference in its entirety. U.S. non-provisionalpatent application Ser. No. 15/063,305 claims priority under 35 U.S.C.§120 to, and is a continuation of, U.S. non-provisional patentapplication Ser. No. 14/037,608, filed on Sep. 26, 2013, entitled“Speaker Cooling,” which issued as U.S. Pat. No. 9,354,677 on May 31,2016, and which is incorporated herein by reference in its entirety.

FIELD OF THE DISCLOSURE

The disclosure is related to consumer goods and, more particularly, tomethods, systems, products, features, services, and other items directedto media playback or some aspect thereof.

BACKGROUND

Digital music has become readily available due in part to thedevelopment of consumer level technology that has allowed people tolisten to digital music on a personal audio device. The consumer'sincreasing preference for digital audio has also resulted in theintegration of personal audio devices into PDAs, cellular phones, andother mobile devices. The portability of these mobile devices hasenabled people to take the music listening experience with them andoutside of the home. People have become able to consume digital music,like digital music files or even Internet radio, in the home through theuse of their computer or similar devices. Now there are many differentways to consume digital music, in addition to other digital contentincluding digital video and photos, stimulated in many ways byhigh-speed Internet access at home, mobile broadband Internet access,and the consumer's hunger for digital media.

Until recently, options for accessing and listening to digital audio inan out-loud setting were severely limited. In 2005, Sonos offered forsale its first digital audio system that enabled people to, among manyother things, access virtually unlimited sources of audio via one ormore networked connected zone players, dynamically group or ungroup zoneplayers upon command, wirelessly send the audio over a local networkamongst zone players, and play the digital audio out loud acrossmultiple zone players in synchrony. The Sonos system can be controlledby software applications running on network capable mobile devices andcomputers.

Given the insatiable appetite of consumers towards digital media, therecontinues to be a need to develop consumer technology thatrevolutionizes the way people access and consume digital media.

BRIEF DESCRIPTION OF THE DRAWINGS

Features, aspects, and advantages of the presently disclosed technologymay be better understood with regard to the following description,appended claims, and accompanying drawings where:

FIG. 1 shows an example configuration in which certain embodiments maybe practiced;

FIG. 2A shows an illustration of an example zone player having abuilt-in amplifier and transducers;

FIG. 2B shows an illustration of an example zone player having abuilt-in amplifier and connected to external speakers;

FIG. 2C shows an illustration of an example zone player connected to anA/V receiver and speakers;

FIG. 3 shows an internal functional block diagram of an example zoneplayer;

FIG. 4 shows an example playback queue configuration for a network mediasystem;

FIG. 5 shows an illustration of an example speaker cooling one or morecomponents in an example zone player;

FIG. 6A shows a graph demonstrating example temperatures over time ofvarious components in an example zone player;

FIG. 6B shows a graph demonstrating example temperatures over time ofvarious components in a zone player with speaker cooling using inaudibleaudio; and

FIG. 7 shows an example flow diagram for cooling one or more componentsin an example zone player by playing inaudible audio content.

In addition, the drawings are for the purpose of illustrating exampleembodiments, but it is understood that the inventions are not limited tothe arrangements and instrumentality shown in the drawings.

DETAILED DESCRIPTION I. Overview

Embodiments described herein involve speaker cooling using inaudibleaudio content in a playback device based on temperatures of componentsand/or presence of audible audio content. In one example, a household ofa user may include one or more playback devices configured as a networkmedia system. In discussions herein, playback devices may also bereferred to as zone players. Each playback device in the one or moreplayback devices may include one or more components. The one or morecomponents may include a processor module, a memory, a power supply, anaudio amplifier, and one or more speakers, for example. In some cases,the processor module and/or other components of the playback device mayremain “active” even when the playback device is not outputting audiocontent. For discussions herein, however, a playback device in the oneor more playback devices may be considered to be in an “active state”when the playback device is outputting audible audio content and may beconsidered to be in an “inactive state” when the playback device is notoutputting audible audio content, even if the processor module remainsactive.

The one or more components of the playback device may each generate heatat different rates, whether the playback device is in the active stateor the inactive state. In a case the playback device is in the activestate, audio playback by the one or more speakers of the playback devicemay generate air movement that may contribute to a cooling of some orall of the one or more components. Cooling in this context may refer todispersing heat away from some of the one or more components andeffectively lowering of temperature around those components. When theplayback device is no longer active, however, cooling of some or all ofthe one or more components may be reduced because the speaker may nolonger be generating air movement that may contribute to the cooling.Further, as indicated above, some of the one or more components of theplayback device may remain active even when the playback device is inthe inactive state. As such, when the playback device is no longer inthe active state, temperatures for some of the one or more componentsmay continue to increase, without air movement generated from thespeakers to contribute to cooling.

The playback device may be in a sealed enclosure or in a portedenclosure. As such, in some cases, cooling of the one or more componentsmay vary depending on the type of enclosure the playback device is in,and where within the enclosure each of the one or more components may bepositioned.

In one example, the playback device may be configured to play inaudibleaudio content when the playback device is in the inactive state, suchthat air movement may be generated by the one or more speakers tocontribute to the cooling of some or all of the one or more componentsin the playback device.

In another example, one or more thermal sensors in the playback devicemay be configured to detect a temperature on or around the one or morecomponents. When a detected temperature on or around the one or morecomponents is higher than a first predetermined threshold value, theplayback device may be configured to play inaudible audio content. Inthis context, the inaudible audio content may include inaudiblefrequencies that, when played by the playback device, may cause at leastone of the one or more speakers to vibrate. The vibration of the atleast one of the one or more speakers may result in movement of air thatmay contribute to the cooling of at least one of the one or morecomponents, as discussed above.

As mentioned, the inaudible audio content may include frequencies withina frequency range inaudible to an average human being. In one example,the frequency range may include frequencies outside the range of 20 Hzto 20 kHz. In example embodiment, the one or more speakers may playaudio content from one or more frequency ranges. For instance, one ofthe one or more speakers may play audio content from a frequency rangebelow 20 Hz, a frequency range above 20 kHz, or may play audio contentin both frequency ranges below 20 Hz and above 20 kHz. The frequencyrange or ranges of the inaudible audio content may be predetermined ormay be randomly selected by the playback device. Further, each of theone or more speakers may play inaudible audio content from the samefrequency range or from different frequency ranges. Other examples arealso possible.

The playback device may be configured to play the inaudible audiocontent when a determination is made that the playback device is nolonger playing audible audio content. Determination of whether theplayback device is playing audible audio content may be performed by aprocessor module or an audio processing component of the playbackdevice, among others. There may be one or more indicators that may helpdetermine whether an audible audio content is playing.

A first example indicator may be that the playback device is streamingaudio content from a playback queue. A second example indicator may bethat an input has been received to cause the playback device to playchosen audio content. In one instance, the input may be received from acontroller in communication with the playback device. A third exampleindicator may be the playback of audio content, such as audio contenthaving frequencies between 20 Hz and 20 kHz. More specifically, aprocessor may be configured analyze the audio content being played bythe playback device and determine whether the audio content includesfrequencies between 20 Hz and 20 kHz. One having ordinary skill in theart will appreciate that audible audio content in some cases may alsoinclude frequencies below 20 Hz and above 20 kHz. The indicatorsdiscussed may be used in any combination to determine that audible audiocontent is being played by the playback device. Other indicators arepossible as well.

In one case, the playback device may be configured to stop playing theinaudible audio content when the temperature of one or more componentsis below a second predetermined threshold. Stopping playback of theinaudible audio content may be performed by one or more components suchas a processor of the playback device. In one example, the firstpredetermined threshold mentioned above and second predeterminedthreshold may be the same for each of the one or more components. Inanother case, the first predetermined threshold and second predeterminedthreshold may be different for one or more of the one or morecomponents. Other examples are also possible.

In another case, the playback device may be configured to stop playingthe inaudible audio content when the playback device begins to playaudible audio content. As described above, there may be several exampleindicators that may be based on to determine that the playback device isplaying, or will be playing audible audio content. In this case,stopping playback of the inaudible audio content may also be done by oneor more components such as a processor.

As indicated above, the present application involves speaker coolingusing inaudible audio content in a playback device based on temperatureof components and/or presence of audible audio content. In one aspect, amethod is provided. The method involves determining, based on adetection by a thermal sensor, a temperature on or around one or morecomponents that are located within a sealed enclosure of a playbackdevice. The playback device comprises at least one speaker configured toplay audio content. The method also involves determining that thetemperature is greater than a predetermined value and responsivelycausing the at least one speaker to play inaudible audio content. Theplayback of inaudible audio content causes the at least one speaker tovibrate and disperse heat away from the one or more components.

In another aspect, a second method is provided. The method involvesdetermining, based on detection by a thermal sensor, whether atemperature of at least a portion of the playback device is above afirst predetermined temperature. The method further involvesdetermining, based on detection by a thermal sensor, whether atemperature of at least a portion of the playback device is above afirst predetermined temperature. The method also involves determining bythe playback device whether the playback device is playing audible audiocontent through the speaker and playing inaudible audio content by theplayback device when: (i) the temperature of the at least a portion ofthe playback device is determined to be above the first predeterminedtemperature, and (ii) the playback device is determined to not beplaying audible audio content.

In yet another aspect, a non-transitory computer readable storage mediumis provided. The non-transitory computer readable storage mediumincludes a set of instructions for execution by a processor. The set ofinstructions, when executed, cause a playback device to determinewhether a temperature of at least a portion of the playback device isabove a first predetermined temperature. The set of instructions, whenexecuted, also cause a playback device to determine whether the playbackdevice is playing audible audio content and play inaudible audio contentwhen: (i) the temperature of the at least a portion of the playbackdevice is determined to be above the first predetermined temperature,and (ii) the playback device is determined not to be playing audibleaudio content.

Other embodiments, as those discussed in the following and others as canbe appreciated by one having ordinary skill in the art are alsopossible.

II. Example Operating Environment

Referring now to the drawings, in which like numerals can refer to likeparts throughout the figures, FIG. 1 shows an example media systemconfiguration 100 in which one or more embodiments disclosed herein canbe practiced or implemented.

By way of illustration, the media system configuration 100 is associatedwith a home having multiple zones, although it should be understood thatthe home could be configured with only one zone. Additionally, one ormore zones can be added to the configuration 100 over time. Each zonemay be assigned by a user to a different room or space, such as, forexample, an office, bathroom, bedroom, kitchen, dining room, familyroom, home theater room, utility or laundry room, and patio. A singlezone might also include multiple rooms or spaces if so configured. Withrespect to FIG. 1, one or more of zone players 102-124 are shown in eachrespective zone. Zone players 102-124, also referred to herein asplayback devices, multimedia units, speakers, players, and so on,provide audio, video, and/or audiovisual output. A controller 130 (e.g.,shown in the kitchen for purposes of this illustration) provides controlto the media system configuration 100. Controller 130 may be fixed to azone, or alternatively, mobile such that it can be moved about thezones. The media system configuration 100 may also include more than onecontroller 130, and additional controllers may be added to the systemover time.

The media system configuration 100 illustrates an example whole housemedia system, though it is understood that the technology describedherein is not limited to, among other things, its particular place ofapplication or to an expansive system like a whole house media system100 of FIG. 1.

a. Example Zone Players

FIGS. 2A, 2B, and 2C show example types of zone players. Zone players200, 202, and 204 of FIGS. 2A, 2B, and 2C, respectively, can correspondto any of the zone players 102-124 of FIG. 1, for example. In someembodiments, audio is reproduced using only a single zone player, suchas by a full-range player. In some embodiments, audio is reproducedusing two or more zone players, such as by using a combination offull-range players or a combination of full-range and specializedplayers. In some embodiments, zone players 200-204 may also be referredto as a “smart speaker,” because they contain processing capabilitiesbeyond the reproduction of audio, more of which is described below.

FIG. 2A illustrates a zone player 200 that includes sound producingequipment 208 capable of reproducing full-range sound. The sound maycome from an audio signal that is received and processed by zone player200 over a wired or wireless data network. Sound producing equipment 208includes one or more built-in amplifiers and one or more acoustictransducers (e.g., speakers). A built-in amplifier is described morebelow with respect to FIG. 3. A speaker or acoustic transducer caninclude, for example, any of a tweeter, a mid-range driver, a low-rangedriver, and a subwoofer. In some embodiments, zone player 200 can bestatically or dynamically configured to play stereophonic audio,monaural audio, or both. In some embodiments, zone player 200 may bedynamically configured to reproduce a subset of full-range sound, suchas when zone player 200 is grouped with other zone players to playstereophonic audio, monaural audio, and/or surround audio or when themedia content received by zone player 200 is less than full-range.

FIG. 2B illustrates zone player 202 that includes a built-in amplifierto power a set of detached speakers 210. A detached speaker can include,for example, any type of loudspeaker. Zone player 202 may be configuredto power one, two, or more separate loudspeakers. Zone player 202 may beconfigured to communicate an audio signal (e.g., right and left channelaudio or more channels depending on its configuration) to the detachedspeakers 210 via a wired path.

FIG. 2C illustrates zone player 204 that does not include a built-inamplifier, but is configured to communicate an audio signal, receivedover a data network, to an audio (or “audio/video”) receiver 214 withbuilt-in amplification.

Referring back to FIG. 1, in some embodiments, one, some, or all of thezone players 102 to 124 can retrieve audio directly from a source. Forexample, a particular zone player in a zone or zone group may beassigned to a playback queue (or “queue”). The playback queue containsinformation corresponding to zero or more audio items for playback bythe associated zone or zone group. The playback queue may be stored inmemory on a zone player or some other designated device. Each itemcontained in the playback queue may comprise a uniform resourceidentifier (URI) or some other identifier that can be used by the zoneplayer(s) to seek out and/or retrieve the audio items from theidentified audio source(s). Depending on the item, the audio sourcemight be found on the Internet (e.g., the cloud), locally from anotherdevice over the data network 128 (described further below), from thecontroller 130, stored on the zone player itself, or from an audiosource communicating directly to the zone player. In some embodiments,the zone player can reproduce the audio itself (e.g., play the audio),send the audio to another zone player for reproduction, or both wherethe audio is reproduced by the zone player as well as one or moreadditional zone players (possibly in synchrony). In some embodiments,the zone player may play a first audio content (or alternatively, maynot play the content at all), while sending a second, different audiocontent to another zone player(s) for reproduction. To the user, eachitem in a playback queue is represented on an interface of a controllerby an element such as a track name, album name, radio station name,playlist, or other some other representation. A user can populate theplayback queue with audio items of interest. The user may also modifyand clear the playback queue, if so desired.

By way of illustration, SONOS, Inc. of Santa Barbara, Calif. presentlyoffers for sale zone players referred to as a “PLAY:5,” “PLAY:3,”“PLAYBAR,” “CONNECT:AMP,” “CONNECT,” and “SUB.” Any other past, present,and/or future zone players can additionally or alternatively be used toimplement the zone players of example embodiments disclosed herein.Additionally, it is understood that a zone player is not limited to theparticular examples illustrated in FIGS. 2A, 2B, and 2C or to the SONOSproduct offerings. For example, a zone player may include a wired orwireless headphone. In yet another example, a zone player might includea sound bar for television. In yet another example, a zone player mayinclude or interact with a docking station for an Apple iPod™ or similardevice.

b. Example Data Connection

Zone players 102-124 of FIG. 1 are coupled directly or indirectly to adata network, such as data network 128. Controller 130 may also becoupled directly or indirectly to data network 128 or individual zoneplayers. Data network 128 is represented by an octagon in the figure tostand out from other representative components. While data network 128is shown in a single location, it is understood that such a network isdistributed in and around system 100. Particularly, data network 128 canbe a wired network, a wireless network, or a combination of both wiredand wireless networks. In some embodiments, one or more of the zoneplayers 102-124 are wirelessly coupled to data network 128 based on aproprietary mesh network. In some embodiments, one or more of the zoneplayers are coupled to data network 128 using a centralized access pointsuch as a wired or wireless router. In some embodiments, one or more ofthe zone players 102-124 are coupled via a wire to data network 128using Ethernet or similar technology. In addition to the one or morezone players 102-124 connecting to data network 128, data network 128can further allow access to a wide area network, such as the Internet.

In some embodiments, connecting any of the zone players 102-124, or someother connecting device, to a broadband router, can create data network128. Other zone players 102-124 can then be added wired or wirelessly tothe data network 128. For example, a zone player (e.g., any of zoneplayers 102-124) can be added to the system configuration 100 by simplypressing a button on the zone player itself (or perform some otheraction), which enables a connection to be made to data network 128. Thebroadband router can be connected to an Internet Service Provider (ISP),for example. The broadband router can be used to form another datanetwork within the system configuration 100, which can be used in otherapplications (e.g., web surfing). Data network 128 can also be used inother applications, if so programmed. An example, second network mayimplement SONOSNET™ protocol, developed by SONOS, Inc. of Santa Barbara.SONOSNET™ represents a secure, AES-encrypted, peer-to-peer wireless meshnetwork. Alternatively, in certain embodiments, the data network 128 isthe same network, such as a traditional wired or wireless network, usedfor other applications in the household.

c. Example Zone Configurations

A particular zone can contain one or more zone players. For example, thefamily room of FIG. 1 contains two zone players 106 and 108, while thekitchen is shown with one zone player 102. In another example, the hometheater room contains additional zone players to play audio from a 5.1channel or greater audio source (e.g., a movie encoded with 5.1 orgreater audio channels). In some embodiments, one can position a zoneplayer in a room or space and assign the zone player to a new orexisting zone via controller 130. As such, zones may be created,combined with another zone, removed, and given a specific name (e.g.,“Kitchen”), if so desired and programmed to do so with controller 130.Moreover, in some embodiments, zone configurations may be dynamicallychanged even after being configured using controller 130 or some othermechanism.

In some embodiments, if a zone contains two or more zone players, suchas the two zone players 106 and 108 in the family room, then the twozone players 106 and 108 can be configured to play the same audio sourcein synchrony, or the two zone players 106 and 108 can be paired to playtwo separate sounds in left and right channels, for example. In otherwords, the stereo effects of a sound can be reproduced or enhancedthrough the two zone players 106 and 108, one for the left sound and theother for the right sound. In certain embodiments, paired zone players(also referred to as “bonded zone players”) can play audio in synchronywith other zone players in the same or different zones.

In some embodiments, two or more zone players can be sonicallyconsolidated to form a single, consolidated zone player. A consolidatedzone player (though made up of multiple, separate devices) can beconfigured to process and reproduce sound differently than anunconsolidated zone player or zone players that are paired, because aconsolidated zone player will have additional speaker drivers from whichsound can be passed. The consolidated zone player can further be pairedwith a single zone player or yet another consolidated zone player. Eachplayback device of a consolidated playback device can be set in aconsolidated mode, for example.

According to some embodiments, one can continue to do any of: group,consolidate, and pair zone players, for example, until a desiredconfiguration is complete. The actions of grouping, consolidation, andpairing are preferably performed through a control interface, such asusing controller 130, and not by physically connecting and re-connectingspeaker wire, for example, to individual, discrete speakers to createdifferent configurations. As such, certain embodiments described hereinprovide a more flexible and dynamic platform through which soundreproduction can be offered to the end-user.

d. Example Audio Sources

In some embodiments, each zone can play from the same audio source asanother zone or each zone can play from a different audio source. Forexample, someone can be grilling on the patio and listening to jazzmusic via zone player 124, while someone is preparing food in thekitchen and listening to classical music via zone player 102. Further,someone can be in the office listening to the same jazz music via zoneplayer 110 that is playing on the patio via zone player 124. In someembodiments, the jazz music played via zone players 110 and 124 isplayed in synchrony. Synchronizing playback amongst zones allows for anindividual to pass through zones while seamlessly (or substantiallyseamlessly) listening to the audio. Further, zones can be put into a“party mode” such that all associated zones will play audio insynchrony.

Sources of audio content to be played by zone players 102-124 arenumerous. In some embodiments, audio on a zone player itself may beaccessed and played. In some embodiments, audio on a controller may beaccessed via the data network 128 and played. In some embodiments, musicfrom a personal library stored on a computer or networked-attachedstorage (NAS) may be accessed via the data network 128 and played. Insome embodiments, Internet radio stations, shows, and podcasts may beaccessed via the data network 128 and played. Music or cloud servicesthat let a user stream and/or download music and audio content may beaccessed via the data network 128 and played. Further, music may beobtained from traditional sources, such as a turntable or CD player, viaa line-in connection to a zone player, for example. Audio content mayalso be accessed using a different protocol, such as Airplay™, which isa wireless technology by Apple, Inc., for example. Audio contentreceived from one or more sources can be shared amongst the zone players102 to 124 via data network 128 and/or controller 130. Theabove-disclosed sources of audio content are referred to herein asnetwork-based audio information sources. However, network-based audioinformation sources are not limited thereto.

In some embodiments, the example home theater zone players 116, 118, 120are coupled to an audio information source such as a television 132. Insome examples, the television 132 is used as a source of audio for thehome theater zone players 116, 118, 120, while in other examples audioinformation from the television 132 may be shared with any of the zoneplayers 102-124 in the audio system 100.

III. Example Zone Players

Referring now to FIG. 3, there is shown an example block diagram of azone player 300 in accordance with an embodiment. Zone player 300includes a network interface 302, a processor 308, a memory 310, anaudio processing component 312, one or more modules 314, an audioamplifier 316, and a speaker unit 318 coupled to the audio amplifier316. FIG. 2A shows an example illustration of such a zone player. Othertypes of zone players may not include the speaker unit 318 (e.g., suchas shown in FIG. 2B) or the audio amplifier 316 (e.g., such as shown inFIG. 2C). Further, it is contemplated that the zone player 300 can beintegrated into another component. For example, the zone player 300could be constructed as part of a television, lighting, or some otherdevice for indoor or outdoor use.

In some embodiments, network interface 302 facilitates a data flowbetween zone player 300 and other devices on a data network 128. In someembodiments, in addition to getting audio from another zone player ordevice on data network 128, zone player 300 may access audio directlyfrom the audio source, such as over a wide area network or on the localnetwork. In some embodiments, the network interface 302 can furtherhandle the address part of each packet so that it gets to the rightdestination or intercepts packets destined for the zone player 300.Accordingly, in certain embodiments, each of the packets includes anInternet Protocol (IP)-based source address as well as an IP-baseddestination address.

In some embodiments, network interface 302 can include one or both of awireless interface 304 and a wired interface 306. The wireless interface304, also referred to as a radio frequency (RF) interface, providesnetwork interface functions for the zone player 300 to wirelesslycommunicate with other devices (e.g., other zone player(s), speaker(s),receiver(s), component(s) associated with the data network 128, and soon) in accordance with a communication protocol (e.g., any wirelessstandard including IEEE 802.11a, 802.11b, 802.11g, 802.11n, 802.11ac,802.15, 4G mobile communication standard, and so on). Wireless interface304 may include one or more radios. To receive wireless signals and toprovide the wireless signals to the wireless interface 304 and totransmit wireless signals, the zone player 300 includes one or moreantennas 320. The wired interface 306 provides network interfacefunctions for the zone player 300 to communicate over a wire with otherdevices in accordance with a communication protocol (e.g., IEEE 802.3).In some embodiments, a zone player includes multiple wireless 304interfaces. In some embodiments, a zone player includes multiple wired306 interfaces. In some embodiments, a zone player includes both of theinterfaces 304 and 306. In some embodiments, a zone player 300 includesonly the wireless interface 304 or the wired interface 306.

In some embodiments, the processor 308 is a clock-driven electronicdevice that is configured to process input data according toinstructions stored in memory 310. The memory 310 is data storage thatcan be loaded with one or more software module(s) 314, which can beexecuted by the processor 308 to achieve certain tasks. In theillustrated embodiment, the memory 310 is a tangible machine-readablemedium storing instructions that can be executed by the processor 308.In some embodiments, a task might be for the zone player 300 to retrieveaudio data from another zone player or a device on a network (e.g.,using a uniform resource locator (URL) or some other identifier). Insome embodiments, a task may be for the zone player 300 to send audiodata to another zone player or device on a network. In some embodiments,a task may be for the zone player 300 to synchronize playback of audiowith one or more additional zone players. In some embodiments, a taskmay be to pair the zone player 300 with one or more zone players tocreate a multi-channel audio environment. Additional or alternativetasks can be achieved via the one or more software module(s) 314 and theprocessor 308.

The audio processing component 312 can include one or moredigital-to-analog converters (DAC), an audio preprocessing component, anaudio enhancement component or a digital signal processor, and so on. Insome embodiments, the audio processing component 312 may be part ofprocessor 308. In some embodiments, the audio that is retrieved via thenetwork interface 302 is processed and/or intentionally altered by theaudio processing component 312. Further, the audio processing component312 can produce analog audio signals. The processed analog audio signalsare then provided to the audio amplifier 316 for playback throughspeakers 318. In addition, the audio processing component 312 caninclude circuitry to process analog or digital signals as inputs to playfrom zone player 300, send to another zone player on a network, or bothplay and send to another zone player on the network. An example inputincludes a line-in connection (e.g., an auto-detecting 3.5 mm audioline-in connection).

The audio amplifier 316 is a device(s) that amplifies audio signals to alevel for driving one or more speakers 318. The one or more speakers 318can include an individual transducer (e.g., a “driver”) or a completespeaker system that includes an enclosure including one or more drivers.A particular driver can be a subwoofer (e.g., for low frequencies), amid-range driver (e.g., for middle frequencies), and a tweeter (e.g.,for high frequencies), for example. An enclosure can be sealed orported, for example. Each transducer may be driven by its own individualamplifier.

A commercial example, presently known as the PLAY:5™, is a zone playerwith a built-in amplifier and speakers that is capable of retrievingaudio directly from the source, such as on the Internet or on the localnetwork, for example. In particular, the PLAY:5™ is a five-amp,five-driver speaker system that includes two tweeters, two mid-rangedrivers, and one woofer. When playing audio content via the PLAY:5, theleft audio data of a track is sent out of the left tweeter and leftmid-range driver, the right audio data of a track is sent out of theright tweeter and the right mid-range driver, and mono bass is sent outof the subwoofer. Further, both mid-range drivers and both tweeters havethe same equalization (or substantially the same equalization). That is,they are both sent the same frequencies but from different channels ofaudio. Audio from Internet radio stations, online music and videoservices, downloaded music, analog audio inputs, television, DVD, and soon, can be played from the PLAY:5™.

IV. Playback Queue

As discussed above, in some embodiments, a zone player may be assignedto a playback queue identifying zero or more media items for playback bythe zone player. The media items identified in a playback queue may berepresented to the user via an interface on a controller. For instance,the representation may show the user (or users if more than onecontroller is connected to the system) how the zone player is traversingthe playback queue, such as by highlighting the “now playing” item,graying out the previously played item(s), highlighting the to-be-playeditem(s), and so on.

In some embodiments, a single zone player is assigned to a playbackqueue. For example, zone player 114 in the bathroom of FIG. 1 may belinked or assigned to a “Bathroom” playback queue. In an embodiment, the“Bathroom” playback queue might have been established by the system as aresult of the user naming the zone player 114 to the bathroom. As such,contents populated and identified in the “Bathroom” playback queue canbe played via the zone player 114 (the bathroom zone).

In some embodiments, a zone or zone group is assigned to a playbackqueue. For example, zone players 106 and 108 in the family room of FIG.1 may be linked or assigned to a “Family room” playback queue. Inanother example, if family room and dining room zones were grouped, thenthe new group would be linked or assigned to a family room+dining roomplayback queue. In some embodiments, the family room+dining roomplayback queue would be established based upon the creation of thegroup. In some embodiments, upon establishment of the new group, thefamily room+dining room playback queue can automatically include thecontents of one (or both) of the playback queues associated with eitherthe family room or dining room or both. In one instance, if the userstarted with the family room and added the dining room, then thecontents of the family room playback queue would become the contents ofthe family room+dining room playback queue. In another instance, if theuser started with the family room and added the dining room, then thefamily room playback queue would be renamed to the family room+diningroom playback queue. If the new group was “ungrouped,” then the familyroom+dining room playback queue may be removed from the system and/orrenamed to one of the zones (e.g., renamed to “family room” or “diningroom”). After ungrouping, each of the family room and the dining roomwill be assigned to a separate playback queue. One or more of the zoneplayers in the zone or zone group may store in memory the associatedplayback queue.

As such, when zones or zone groups are “grouped” or “ungrouped”dynamically by the user via a controller, the system will, in someembodiments, establish or remove/rename playback queues respectively, aseach zone or zone group is to be assigned to a playback queue. In otherwords, the playback queue operates as a container that can be populatedwith media items for playback by the assigned zone. In some embodiments,the media items identified in a playback queue can be manipulated (e.g.,re-arranged, added to, deleted from, and so on).

By way of illustration, FIG. 4 shows an example network 400 for mediacontent playback. As shown, the example network 400 includes examplezone players 412 and 414, example audio sources 462 and 464, and examplemedia items 420. The example media items 420 may include playlist 422,music track 424, favorite Internet radio station 426, playlists 428 and430, and album 432. In one embodiment, the zone players 412 and 414 maybe any of the zone players shown in FIGS. 1, 2, and 3. For instance,zone players 412 and 414 may be the zone players 106 and 108 in theFamily Room.

In one example, the example audio sources 462 and 464, and example mediaitems 420 may be partially stored on a cloud network. In some cases, theportions of the audio sources 462, 464, and example media items 420 maybe stored locally on one or both of the zone players 412 and 414. In oneembodiment, playlist 422, favorite Internet radio station 426, andplaylist 430 may be stored locally, and music track 424, playlist 428,and album 432 may be stored on the cloud network.

Each of the example media items 420 may be a list of media itemsplayable by a zone player(s). In one embodiment, the example media itemsmay be a collection of links or pointers (i.e., URI) to the underlyingdata for media items that are stored elsewhere, such as the audiosources 462 and 464. In another embodiment, the media items may includepointers to media content stored on the local zone player, another zoneplayer over a local network, or a controller device connected to thelocal network.

As shown, the example network 400 may also include an example queue 402associated with the zone player 412, and an example queue 404 associatedwith the zone player 414. Queue 406 may be associated with a group, whenin existence, comprising zone players 412 and 414. Queue 406 mightcomprise a new queue or exist as a renamed version of queue 402 or 604.In some embodiments, in a group, the zone players 412 and 414 would beassigned to queue 406 and queue 402 and 404 would not be available atthat time. In some embodiments, when the group is no longer inexistence, queue 406 is no longer available. Each zone player and eachcombination of zone players in a network of zone players, such as thoseshown in FIG. 1 or that of example zone players 412, 414, and examplecombination 416, may be uniquely assigned to a corresponding playbackqueue.

A playback queue, such as playback queues 402-406, may includeidentification of media content to be played by the corresponding zoneplayer or combination of zone players. As such, media items added to theplayback queue are to be played by the corresponding zone player orcombination of zone players. The zone player may be configured to playitems in the queue according to a specific order (such as an order inwhich the items were added), in a random order, or in some other order.

The playback queue may include a combination of playlists and othermedia items added to the queue. In one embodiment, the items in playbackqueue 402 to be played by the zone player 412 may include items from theaudio sources 462, 464, or any of the media items 422-432. The playbackqueue 402 may also include items stored locally on the zone player 412,or items accessible from the zone player 414. For instance, the playbackqueue 402 may include Internet radio 426 and album 432 items from audiosource 462, and items stored on the zone player 412.

When a media item is added to the queue via an interface of acontroller, a link to the item may be added to the queue. In a case ofadding a playlist to the queue, links to the media items in the playlistmay be provided to the queue. For example, the playback queue 402 mayinclude pointers from the Internet radio 426 and album 432, pointers toitems on the audio source 462, and pointers to items on the zone player412. In another case, a link to the playlist, for example, rather than alink to the media items in the playlist may be provided to the queue,and the zone player or combination of zone players may play the mediaitems in the playlist by accessing the media items via the playlist. Forexample, the album 432 may include pointers to items stored on audiosource 462. Rather than adding links to the items on audio source 462, alink to the album 432 may be added to the playback queue 402, such thatthe zone player 412 may play the items on the audio source 462 byaccessing the items via pointers in the album 432.

In some cases, contents as they exist at a point in time within aplayback queue may be stored as a playlist, and subsequently added tothe same queue later or added to another queue. For example, contents ofthe playback queue 402, at a particular point in time, may be saved as aplaylist, stored locally on the zone player 412 and/or on the cloudnetwork. The saved playlist may then be added to playback queue 404 tobe played by zone player 414.

V. Example Speaker Cooling Using Inaudible Audio Content

As discussed above, embodiments described herein involve speaker coolingusing inaudible audio content in a playback device based on temperatureof components and/or presence of audible audio content.

a. Example Component Cooling by Speaker Movement

FIG. 5 shows an example of component cooling via speaker movement withinan enclosure of a playback device 500 using airflow generated frommovement of one or more speakers of the playback device. Zone playercomponents 502 may include any or all of the components of zone player300 as described above in association with FIG. 3. The first componentshown may be processor 504, which may be the processor 308 of FIG. 3.The second component shown may be audio amplifier 506, which may be theaudio amplifier 316 of FIG. 3. FIG. 5 also shows a thermal sensor 508,speaker 510, vibrations 512 and air molecules 514.

The thermal sensor 508 may be any device, such as a thermocouple,capable of detecting temperature. The thermal sensor may be configuredto detect temperatures on or around one or more of the zone playercomponents 502. The thermal sensor 508 may have one or more leads thatmay be positioned on or around any number of zone player components 502.Processor 504 and any of the other zone player components 502 may beconnected to the thermal sensor 508 as demonstrated in FIG. 5. Further,the processor 504 may determine, based on a detection by the thermalsensor 508, that a predetermined temperature threshold is reached (suchas thresholds 616 and 618 discussed below in association with FIG. 6B).

Speaker 510 may be the speaker(s) 318 of FIG. 3 as described above.While FIG. 5 shows only one speaker 510, the playback device 500 mayinclude more than one speaker. Speaker 510 may be connected to audioamplifier 506 and any of the other zone player components 502, such asprocessor 504. The connection may allow one or more of the components,such as processor 504, to determine whether an audible audio content isplaying.

In one example, the speaker may be configured to play inaudible audiocontent to assist with cooling components in the playback device when adetermination has been made that an audible signal is no longer beingplayed by the playback device and/or a determination has been made thatthe temperature of one or more zone player components 502, such asprocessor 504, is greater than a predetermined threshold. Subsequently,the speaker 510 may be configured to play inaudible audio content, whichmay result in vibrations 512. The vibrations 512 may cause the movementof air molecules 514 within the enclosure of playback device 500. Themovement of air molecules 514 can result in the cooling of the one ormore zone player components 502 exceeding the predetermined temperaturethreshold as demonstrated by the cooling of processor 504 in curve 614of FIG. 6B.

Further, the processor 504 may generate less thermal energy when causingthe playback device to play inaudible audio content than when theprocessor 504 is causing the playback device to play audible audiocontent. In one case, a signal file for storing the inaudible audiocontent to be played by the playback device may be stored locally on theplayback device. As such, the playback device may not need tocommunicate, or stream audio content over a network when playing theinaudible content and accordingly may require less processing power (andthus less heat generation) than when streaming audio content from anexternal source. In another example, the signal file for storing theinaudible audio content may be simpler and easier to process thanaudible content, and may therefore require less processing power. Ineither case, playback of inaudible audio content may require lessprocessing power from the processor 604 than playback of audible audiocontent, and accordingly generate less heat. As such, the overalltemperature of playback device 500 and/or the temperatures of the one ormore components of the playback device 500 may decrease while playinginaudible audio content because the overall heat gradient may benegative rather than constant.

In addition, speaker 510 may be configured to stop playing the inaudibleaudio content as soon as temperatures of the one or more zone playercomponents 502 detected the thermal sensor 508 are below a secondpredetermined temperature threshold. In another example, the speaker 510may also be configured to stop playing the inaudible audio content assoon as one or more zone player components 502, such as the processor504, determines that audible audio content is to be played by playbackdevice 500.

b. Example Playback Device Component Temperature Graphs

FIGS. 6A and 6B feature graphs 600 and 604, respectively, showingexample temperatures over time on or around one or more components ofthe playback device or zone player. The temperatures may be measuredusing, for example, thermal sensor 508 describe above with respect toFIG. 5. The values of the example temperature and time on or around eachcomponent may differ for each zone player and for each instance that thevalues are recorded. It should be understood that curves 608, 610, 612and 614 and the values represented by the curves are exemplary, and thatother values and curves may be possible. Legends 602 and 606 mayindicate the component represented by each curve. As suggested above,graphs 600 and 604 may show example temperatures over time on or arounda processor, other components, and/or portions of the playback device.As shown, graphs 600 and 604 may provide the parameter of temperature onthe vertical axis using the unit of Celsius and the parameter of time onthe horizontal axis using the unit of minutes. However, each parametermay be represented on either axis while other units of temperature suchas Fahrenheit and other units of time such as seconds may be used. Inone example, both graphs 600 and 604 may show the temperature on oraround the components as the playback device is playing audio content ata certain volume level for sixty minutes before stopping playback orreducing playback to a substantially lower volume level after sixtyminutes. In other words, the playback device may be in an active statefor sixty minutes before entering an inactive state, in the caseplayback is stopped.

Curve 608 of graph 600 and curve 612 of graph 604 may both show theexample temperatures over time on or around “other components” in theplayback device that do not include the processor. “Other components”may represent one or all of the components in the playback device thatare not the processor. As one example, the “other components” mayinclude the amplifier 506 in FIG. 5. Curves 608 and 612 may indicatethat the temperatures on or around “other components” may increase overtime as the playback device is playing audio content at a certainvolume. At the sixty-minute mark, the playback device may enter theinactive state or continue playing audio content at a substantiallylower volume. After the sixty-minute mark, curves 608 and 612demonstrate that the temperature on or around “other components” maydecrease.

Curve 610 of graph 600 shows the example temperatures over time on oraround the playback device's processor. The processor may be theprocessor 504 shown in FIG. 5. As shown, the temperature on or aroundthe processor may increase over time while the playback device may beplaying audio content at a certain volume. At the sixty minute mark, theplayback device may enter the inactive state or continue playing audiocontent at a substantially lower volume. After the sixty minute mark,curve 610 demonstrates that the temperature on or around the processormay temporarily increase before slowly decreasing.

The change in temperature over time as shown by curve 610 can beexplained as follows. When the playback device is at a state of playingaudio content at certain volume, a certain amount of heat or thermalenergy may be present in the enclosure of the playback device. Thethermal energy may be generated by one or more components. Due to themovement of the speaker while the zone player is playing audio contentat maximum volume, movement of air molecules occurs and the thermalenergy may be spread evenly throughout the enclosure. The air movementmay stop when the playback device is no longer playing audio contentbecause the movement of the speaker may have stopped with the stoppingof audio playback. Nevertheless, the thermal energy may still be presentin the enclosure. Further, at the time when audible audio content is nolonger playing, some components such as a processor, may still be activeand therefore may continue to generate thermal energy. Such componentsmay create hot pockets of air that can have a temperature even higherthan the temperature on or around the component at the time audiocontent was playing at maximum volume. These components may eventuallycool down to lower temperatures but this can occur at a slow andundesirable rate.

Curve 614 of graph 604 shows the example temperatures over time on oraround a processor in an example embodiment of the present application.The temperatures of curve 614 may increase in the same manner as curve610 while the playback device is playing audio content at a certainvolume. At the sixty minute mark the audio content may enter theinactive state or continue playing audio content at substantially lowervolume and the temperatures on or around the processor may temporarilyincrease. As discussed above, a speaker of the playback device, such asspeaker(s) 318 of FIG. 3 may play an inaudible audio content as soon asthe first predetermined temperature threshold 616 is reached. Theinaudible audio content may cause the speakers to move and generate airmovement that may help cooling of the processor. As shown by curve 614,the temperature on or around the processor may cool and the playbackdevice may stop playing the inaudible audio content when the temperatureon or around the processor drops to a second predetermined temperaturethreshold 618. Other similar examples involving one or more othercomponents in the playback device may also be possible.

The predetermined temperature thresholds discussed above may beestablished as follows. In one example, a case limit temperature of alowest margin component may be determined to be 92° C. A temperatureoffset between the lowest margin component and the processor may bedetermined to be 8° C. The threshold may thus be determined bysubtracting the temperature offset from the case limit temperature andthen subtracting an additional margin (which may be 5° C.) resulting ina second predefined temperature threshold of 79° C. Other examplesinvolving the establishment of predefined temperature thresholds mayalso be possible.

c. Example Method for Cooling of Playback Device Components

FIG. 7 shows an example flow diagram for speaker cooling using inaudibleaudio content based on temperature of components and presence of audibleaudio content, in accordance with at least some embodiments describedherein. Method 700 shown in FIG. 7 presents an embodiment of a methodthat can be used in environments 100 and 400 as well as systems 200,202, 204, and 500 for example. Method 700 may include one or moreoperations, functions, or actions as illustrated by one or more ofblocks 702-710. Although the blocks are illustrated in sequential order,these blocks may also be performed in a different order than thosedescribed herein. Also, the various blocks may be combined into fewerblocks, divided into additional blocks, and/or removed based upondesired implementation.

In addition, for the method 700 and other processes and methodsdisclosed herein, the flowchart shows functionality and operation of onepossible implementation of present embodiments. In this regard, eachblock may represent a module, a segment, or a portion of program code,which includes one or more instructions executable by a processor forimplementing specific logical functions or steps in the process. Theprogram code may be stored on any type of computer readable medium, forexample, such as a storage device including a disk or hard drive. Thecomputer readable medium may include non-transitory computer readablemedium, for example, such as computer-readable media that stores datafor short periods of time like register memory, processor cache andRandom Access Memory (RAM). The computer readable medium may alsoinclude non-transitory media, such as secondary or persistent long termstorage, like read only memory (ROM), optical or magnetic disks,compact-disc read only memory (CD-ROM), for example. The computerreadable media may also be any other volatile or non-volatile storagesystems. The computer readable medium may be considered a computerreadable storage medium, for example, or a tangible storage device. Inaddition, for the method 700 and other processes and methods disclosedherein, each block in FIG. 7 may represent circuitry that is wired toperform the specific logical functions in the process.

At block 702, the method 700 may involve determining that a temperatureon or around one or more components is above a first predeterminedtemperature. For illustration purposes, the components discussedhereafter may be any of the zone player components 502 described abovein connection with FIG. 5. The first predetermined temperature may be athreshold temperature such as the predetermined temperature threshold616 described above in connection with FIG. 6B. In one example, thetemperature on or around a processor (such as processor 504 of FIG. 5)may be determined to be above a first predetermined temperature. In somecases, each component or portion of the playback device may havedifferent predetermined temperature thresholds.

At block 704, the method 700 may involve determining that the playbackdevice is not playing audible audio content. As indicated above, one ormore of several indicators may be used to determine whether the playbackdevice is playing audible audio content. A first indicator may be thatthe playback device is playing audio content identified in a play queue(such as playback queue 404 described above in association with FIG. 4).A second indicator may be that the playback device has received aninstruction to play audio content. The playback device may receiveinstruction from a user via a controller, as well as otherpossibilities. A third indicator may be the playback of audio content,such as audio content having frequencies between 20 Hz and 20 kHz. Morespecifically, a processor may analyze the audio content and determinewhether the audio content includes frequencies between 20 Hz and 20 kHz.A frequency range between 20 Hz and 20 kHz may be considered as theaudible hearing range for a human. Audible audio content may comprisefrequencies in said range but may also comprise of inaudible frequenciesbelow 20 Hz and/or above 20 kHz. Other indicators may also be possible.

At block 706, the method 700 may involve playing inaudible audiocontent. One or more speakers, such as speaker(s) 318 described above inassociation with FIG. 3, may be configured to play the inaudible audiocontent. The inaudible audio content can cause the speaker to vibrate,which may result in movement of air molecules. The movement of airmolecules may thus disperse the thermal energy away from the one or morecomponents of the playback device, as described above in connection toFIG. 5.

In one example, the inaudible audio content may include one or morefrequencies below 20 Hz. In another example, the inaudible audio contentmay include one or more frequencies above 20 kHz. The inaudible audiocontent in this example may include any number of frequencies below 20Hz and/or above 20 kHz, in any possible combination. The frequenciesused may be predetermined or may be randomly chosen by one or morecomponents of the playback device. The inaudible frequencies may bechosen in association with how much air movement is required in order todisperse heat away from the one or more components at a certain rateand/or until a certain temperature is reached. All speakers may play thesame set of one or more frequencies or each speaker may play a differentset of one or more frequencies. Other examples are also possible.

Further, an example embodiment may include at least two speakers suchthat the inaudible audio content played by one speaker is out of phasewith the inaudible audio content played by the other speaker. In thisembodiment, playback of out of phase audio signals may (1) minimizeaudibility of the audio content being played, (2) result in increasedinternal air movement in the enclosure of the playback device such thatthe heat may disperse more rapidly, and (3) help maintain the pressureinside the enclosure of the playback device. In some cases, maintainingthe pressure inside the enclosure may reduce the power required forgenerating air movement.

At block 708, the method 700 may involve determining that the playbackdevice is to play audible audio content. One or more components of theplayback device may be configured to determine that audible audiocontent is to be played by the playback device using one or more of theindicators discussed above. At block 710, the method 700 may involvedetermining that the temperature on or around one or more components isbelow a second predetermined temperature. To illustrate, a secondpredetermined temperature may be a threshold such as the predeterminedtemperature threshold 618 described above in association with FIG. 6B.In one example, the temperature on or around a processor (such as theprocessor in association with curve 614 of FIG. 6B) may decrease to atemperature below a second predetermined temperature partially as aresult of the cooling effect generated from movements of the speakersplaying inaudible audio content.

At block 712, the method 700 may involve stopping playback of inaudibleaudio content. As indicated above, stopping playback of inaudible audiocontent may be in response to determining that the playback device is toplay audible audio content as discussed in connection to block 708and/or determining that the temperature on or around one or morecomponents is below a second predetermined temperature as discussed inconnection to block 710. Stopping playback of inaudible audio contentmay be done by one or more components, such as a processor or an audioprocessing component (such as processor 308 and audio processingcomponent 312 as described above in association with FIG. 3). In somecases, the temperature on or around the one or more components maycontinue to decline naturally after playback of inaudible audio contenthas stopped.

VI. Conclusion

As indicated above, the present application involves speaker coolingusing inaudible audio content in a playback device based on temperatureof components and/or presence of audible audio content. In one aspect, amethod is provided. The method involves determining, based on adetection by a thermal sensor, a temperature on or around one or morecomponents that are located within a sealed enclosure of a playbackdevice. The playback device comprises at least one speaker configured toplay audio content. The method also involves determining that thetemperature is greater than a predetermined value and responsivelycausing the at least one speaker to play inaudible audio content. Theplayback of inaudible audio content causes the at least one speaker tovibrate and disperse heat away from the one or more components.

In another aspect, a second method is provided. The method involvesdetermining, based on detection by a thermal sensor, whether atemperature of at least a portion of the playback device is above afirst predetermined temperature. The method further involvesdetermining, based on detection by a thermal sensor, whether atemperature of at least a portion of the playback device is above afirst predetermined temperature. The method also involves determining bythe playback device whether the playback device is playing audible audiocontent through the speaker and playing inaudible audio content by theplayback device when: (i) the temperature of the at least a portion ofthe playback device is determined to be above the first predeterminedtemperature, and (ii) the playback device is determined to not beplaying audible audio content.

In yet another aspect, a non-transitory computer readable storage mediumis provided. The non-transitory computer readable storage mediumincludes a set of instructions for execution by a processor. The set ofinstructions, when executed, cause a playback device to determinewhether a temperature of at least a portion of the playback device isabove a first predetermined temperature. The set of instructions, whenexecuted, also cause a playback device to determine whether the playbackdevice is playing audible audio content and play inaudible audio contentwhen: (i) the temperature of the at least a portion of the playbackdevice is determined to be above the first predetermined temperature,and (ii) the playback device is determined not to be playing audibleaudio content.

Additionally, references herein to “embodiment” means that a particularfeature, structure, or characteristic described in connection with theembodiment can be included in at least one example embodiment of theinvention. The appearances of this phrase in various places in thespecification are not necessarily all referring to the same embodiment,nor are separate or alternative embodiments mutually exclusive of otherembodiments. As such, the embodiments described herein, explicitly andimplicitly understood by one skilled in the art, can be combined withother embodiments.

The specification is presented largely in terms of illustrativeenvironments, systems, procedures, steps, logic blocks, processing, andother symbolic representations that directly or indirectly resemble theoperations of data processing devices coupled to networks. These processdescriptions and representations are typically used by those skilled inthe art to most effectively convey the substance of their work to othersskilled in the art. Numerous specific details are set forth to provide athorough understanding of the present disclosure. However, it isunderstood to those skilled in the art that certain embodiments of thepresent disclosure can be practiced without certain, specific details.In other instances, well known methods, procedures, components, andcircuitry have not been described in detail to avoid unnecessarilyobscuring aspects of the embodiments. Accordingly, the scope of thepresent disclosure is defined by the appended claims rather than theforgoing description of embodiments.

We claim:
 1. A playback device, comprising: one or more one processors;at least one speaker; and tangible, non-transitory computer-readablememory having stored instructions that, when executed by the one or moreprocessors, cause the playback device to perform functions comprising:detecting that playback of audible audio content via the at least onespeaker has stopped; and in response to the detection, playing inaudibleaudio content to cause the at least one speaker to vibrate therebyinducing air movement within the playback device.
 2. The playback deviceof claim 1, wherein the audible audio content is a first audible audiocontent, and wherein the functions further comprise: while playing theinaudible audio content, receiving input data indicating an instructionto begin playing a second audible audio content; and based on the inputdata, (i) stopping playback of the inaudible audio content and (ii)beginning playback of the second audible audio content.
 3. The playbackdevice or claim 1, wherein the functions further comprise: while playingthe inaudible audio content, detecting, via a thermal sensor of theplayback device, a temperature of the playback device; determining thatthe temperature is less than a threshold temperature; and stoppingplayback of the inaudible audio content after determining that thetemperature is less than the threshold temperature.
 4. The playbackdevice of claim 1, wherein playing the inaudible audio contentcomprises: playing the inaudible audio content for a pre-determinedduration of time.
 5. The playback device of claim 1, further comprisingat least one thermal sensor, wherein the functions further comprise:detecting, via the at least one thermal sensor, a temperature associatedwith the playback device; and wherein playing the inaudible audiocontent comprises playing the inaudible audio content while the detectedtemperature is greater than a threshold temperature.
 6. The playbackdevice of claim 1, further comprising at least one thermal sensor,wherein the functions further comprise: detecting via the at least onethermal sensor, a temperature associated with the playback device; andprior to playing the inaudible audio content, determining that thetemperature associated with the playback device is above a thresholdtemperature.
 7. The playback device of claim 1, wherein the at least onespeaker comprises one or more first speakers and one or more secondspeakers, and wherein playing the inaudible audio content comprises:causing the one or more first speakers to vibrate; and causing the oneor more second speakers to vibrate out of phase with the one or morefirst speakers.
 8. The playback device of claim 1, wherein the inaudibleaudio content comprises audio content at frequencies above 20 kHz. 9.The playback device of claim 1, wherein the inaudible audio contentcomprises audio content at frequencies below 20 Hz.
 10. Tangible,non-transitory computer-readable media having stored thereoninstructions that, when executed by one or more processors of a playbackdevice, cause the playback device to perform functions comprising:detecting that playback of audible audio content via at least onespeaker of the playback device has stopped; and in response to thedetection, playing inaudible audio content to cause the at least onespeaker to vibrate thereby inducing air movement within the playbackdevice.
 11. The tangible, non-transitory computer-readable media ofclaim 10, wherein the audible audio content is a first audible audiocontent, and wherein the functions further comprise: while playing theinaudible audio content, receiving input data indicating an instructionto begin playing a second audible audio content; and based on the inputdata, (i) stopping playback of the inaudible audio content and (ii)beginning playback of the second audible audio content.
 12. Thetangible, non-transitory computer-readable media of claim 10, whereinthe functions further comprise: while playing the inaudible audiocontent, detecting, via at least one thermal sensor of the playbackdevice, a temperature associated with the playback device; determiningthat the temperature is less than a threshold temperature; and stoppingplayback of the inaudible audio content after determining that thetemperature is less than the threshold temperature.
 13. The tangible,non-transitory computer-readable media of claim 10, wherein playing theinaudible audio content comprises: playing the inaudible audio contentfor a pre-determined duration of time.
 14. The tangible, non-transitorycomputer-readable media of claim 10, wherein the functions furthercomprise: detecting, via a thermal sensor of the playback device, atemperature of the playback device; and wherein playing the inaudibleaudio content comprises playing the inaudible audio content while thedetected temperature is greater than a threshold temperature.
 15. Thetangible, non-transitory computer-readable medium of claim 10, whereinthe functions further comprise: detecting, via a thermal sensor of theplayback device, a temperature associated with the playback device; andprior to playing the inaudible audio content, determining that thetemperature associated with the playback device is above a thresholdtemperature.
 16. A method comprising: detecting, via a playback device,that playback of audible audio content via at least one speaker of theplayback device has stopped; and in response to the detection, playing,via the playback device, inaudible audio content to cause the at leastone speaker to vibrate thereby inducing air movement within the playbackdevice.
 17. The method of claim 16, wherein the audible audio content isa first audible audio content, and wherein the method further comprises:while the playback device is playing the inaudible audio content,rece1vmg, via the playback device, input data indicating an instructionto begin playing a second audible audio content; and based on the inputdata, (i) stopping playback of the inaudible audio content and (ii)beginning, via the playback device, playback of the second audible audiocontent.
 18. The method of claim 16, further comprising: while theplayback device is playing the inaudible audio content, detecting, viaat least one thermal sensor of the playback device, a temperatureassociated with the playback device; determining, via the playbackdevice, that the temperature is less than a threshold temperature; andstopping playback of the inaudible audio content after determining thatthe temperature is less than the threshold temperature.
 19. The methodof claim 16, further comprising: detecting, via at least one thermalsensor of the playback device, a temperature associated with theplayback device; and wherein playing the inaudible audio contentcomprises playing the inaudible audio content while the detectedtemperature is greater than a threshold temperature.
 20. The method ofclaim 16, further comprising: detecting, via at least one thermal sensorof the playback device, a temperature associated with the playbackdevice; and prior to playing the inaudible audio content, determiningthat the temperature associated with the playback device is above athreshold temperature.